In road traffic, sets of traffic lights are frequently used to control the flow of traffic. The sets of traffic lights are usually assigned a stop line which a vehicle can pass in a first operating state of the set of traffic lights, while vehicles are not permitted to cross the stop line in a second operating state of the set of traffic lights. The first operating state of the set of traffic lights is usually indicated by a red light, and the second operating state by a green light.
Serious accidents often occur when a vehicle travels over the stop line assigned to a set of traffic lights when the lights are red. The cause for this may be, for example, that the driver of the vehicle has simply not noticed the set of traffic lights. Furthermore, the vehicle operators generally find it disruptive to have to stop their vehicle at a set of traffic lights. Although this could often be prevented by setting a suitable vehicle speed when approaching the set of traffic lights, it is generally not possible for the driver to determine this.